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651.
Investigations of place have often focused on either place meaning (utilizing interpretive designs) or place attachment (using quantitative measures). Rarely have researchers explored the association between place meaning and place attachment. Hence, this investigation was designed to explore how individuals' attachment to a natural environment is reflected in their depictions of why the resource is meaningful. 相似文献
652.
653.
This paper evaluates the feasibility of establishing a multiple-use marine protected area. The methodology was applied to evaluate three proposed sites in Chile with diverse conservation needs, social stress and poverty levels, and different economic activities (small-scale fishing, heavy industry, and mining activities). We use two broad categories for the evaluation: socio-economic and political–institutional. The methodology uses a combination of secondary data with personal interviews, workshops, and focus groups with stakeholders (e.g., fishermen, unions, politicians, social organizations) from different political, social, and economic backgrounds to characterize current and potential natural and social resources and to evaluate in an ordinal scale the feasibility of establishing the protected area. The methodology allows us to correctly identify the challenges faced in each site and can be used to develop appropriate strategies for balancing economic, social, and environmental objectives. This methodology can be replicated to evaluate the feasibility of other marine or terrestrial protected areas. 相似文献
654.
The effects of increasing Cu, Ni and Cr concentrations (0.5, 5, 10, 20 and 40 mg L−1) on microtubule organization and the viability of leaf cells of the seagrass Cymodocea nodosa for 13 consecutive days were investigated under laboratory conditions. Increased oblique microtubule orientation, microtubule depolymerization at the 5–40 mg L−1 Ni treatments after 3 d of exposure, and a complete microtubule depolymerization at all Ni treatments after 5 d were observed. Cu depolymerised microtubules after three to 7 d of exposure, while Cr caused an extensive microtubule bundling after 9 or 11 d of exposure, depending on metal dosage. Fluorescence intensity measurements further consolidated the above phenomena. Cell death, occurring at later time than microtubule disturbance, was also observed at all Cu and Ni treatments and at the 10–40 mg L−1 Cr treatments and adding to the above quantification of the number of dead cells clearly showed that only a portion of the cell population studied died. The data presented, being the first assessment of microtubule disturbance in seagrasses, indicate that microtubules in seagrass leaf cells could be used as a valuable and early marker of metal-induced stress in biomonitoring programmes. 相似文献
655.
When spatial fishing data is fed into systematic conservation planning processes the cost to a fishery could be ensured to be minimal in the zoning of marine protected areas. We used vessel monitoring system (VMS) data to map the distribution of prawn trawling and calculate fishing intensity for 1-ha grid cells, in the Kosterhavet National Park (Sweden). We then used the software Marxan to generate cost-efficient reserve networks that represented every biotope in the Park. We asked what were the potential gains and losses in terms of fishing effort and species conservation of different planning scenarios. Given a conservation target of 10 % representation of each biotope, the fishery need not lose more than 20 % of its fishing grounds to give way to cost-efficient conservation of benthic diversity. No additional reserved area was needed to achieve conservation targets while minimizing fishing costs. We discuss the benefits of using VMS data for conservation planning. 相似文献
656.
Nutrient loads from inland sources to the Baltic Sea and adjacent inland waters need to be reduced in order to prevent eutrophication and meet requirements of the European Water Framework Directive (WFD) and the Baltic Sea Action Plan (BSAP). We here investigate the spatial implications of using different possible criteria for reducing water-borne phosphorous (P) loads in the Northern Baltic Sea River Basin District (NBS-RBD) in Sweden. Results show that most catchments that have a high degree of internal eutrophication do not express high export of P from their outlets. Furthermore, due to lake retention, lake catchments with high P-loads per agricultural area (which is potentially of concern for the WFD) did not considerably contribute to the P-loading of the Baltic Sea. Spatially uniform water quality goals may, therefore, not be effective in NBS-RBD, emphasizing more generally the need for regional adaptation of WFD and BSAP-related goals.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-014-0523-x) contains supplementary material, which is available to authorized users. 相似文献657.
S. Alonso-Prez E. Cuevas X. Querol M. Viana J.C. Guerra 《Atmospheric environment (Oxford, England : 1994)》2007,41(40):9468-9480
Six years (1998–2003) of measurements of ambient air concentrations of total suspended particulate (TSP) measured at a rural background monitoring station in Tenerife (Canary Islands), the El Río station (ER, 28°08′35″N, 16°39′20″W, 500 m a.s.l.) were studied. African dust outbreaks were objectively identified using a new quantitative tool, called the African Index. This index indicates the percentage of time that an air mass remained over an African region at one of three possible height intervals of the lower troposphere. After identifying these episodes, a study of the background TSP levels at the ER station and of direct and indirect (those which cause vertical deposition of dust) African air mass intrusion impacts was performed. Taking into account both direct and indirect episodes, a total of 322 days of African dust intrusion were objectively identified (a mean of 54 episodes per year) in the period 1998–2003, some of them caused by “transition episodes” or “return African air masses”. A subjective method confirmed that 256 of these days were caused by direct impacts of African dust on the ER station. A mean TSP value of 21.6 μg m−3 was found at the station during this period. All the episodes occurred when the TSP concentration was >28.5 μg m−3. The TSP background (14 μg m−3) can be assumed to be representative of the MBL of the Eastern North Atlantic subtropical region. The highest number of dust gravitational settlement (or indirect) episodes occurs in summer, but the highest contribution of these episodes to the TSP levels is in March with a monthly mean TSP contribution of up to 30.5 μg m−3. 相似文献
658.
Delineation of soil and groundwater contamination using geophysical methods at a waste disposal site in Çanakkale, Turkey 总被引:1,自引:0,他引:1
Direct current (DC) resistivity, self potential (SP) and very low frequency electromagnetic (VLF-EM) measurements are carried out to detect the spread of groundwater contamination and to locate possible pathways of leachate plumes, that resulted from an open waste disposal site of Canakkale municipality. There is no proper management of the waste disposal site in which industrial and domestic wastes were improperly dumped. Furthermore, because of the dumpsite is being located at the catchment area borders of a small creek and is being topographically at a high elevation relative to the urban area, the groundwater is expected to be hazardously contaminated. Interpretations of DC resistivity geoelectrical data showed a low resistivity zone (<5 ohm-m), which appears to be a zone, that is fully saturated with leachate from an open dumpsite. The VLF-EM and SP method, support the results of geoelectrical method relating a contaminated zone in the survey area. There is a good correlation between the geophysical investigations and the results of previously collected geochemical and hydrochemical measurements. 相似文献
659.
Gouteux B Muir DC Backus S Born EW Dietz R Haug T Metcalfe T Metcalfe C Øien N 《Environmental pollution (Barking, Essex : 1987)》2008,153(1):71-83
Toxaphene contamination of minke whales (Balaenoptera acutorostrata) from North Atlantic waters was examined for the first time. Total toxaphene and SigmaCHB (sum of 11 chlorobornanes) concentrations in blubber samples ranged from 170+/-110 and 41+/-39 ng/g lipid weight (l.w.) for female minke whales from southeastern Greenland to 5800+/-4100 and 1100+/-780 ng/g l.w. for males from the North Sea, respectively. Very large variations in toxaphene concentrations among sampling areas were observed suggesting a spatial segregation of minke whales. However, much of the apparent geographical discrimination was explained by the seasonal fluctuation of animal fat mass. Patterns of CHBs in males revealed that recalcitrant CHBs were in higher proportions in animals from the more easterly areas than in animals from the more westerly areas. This trend may be influenced by the predominance of the US, over the European, input of toxaphene to North Atlantic waters. 相似文献
660.
论我国典型公共场所突发事件现场应急处置中消防部队的主导作用 总被引:5,自引:3,他引:2
消防部队作为应对典型公共场所突发事件的主导救援力量具有独特的优势,并从法律优势、体制优势、装备优势、经验优势、信息化建设优势、地域分布优势和群众信任优势等7个方面获得充分论证。从政府加强法制建设,扩充现有消防人员的编制,进一步加大消防经费投入、加强消防基础设施和装备建设以及加强技术培训、提升消防部队整体实战能力等4个方面提出了保障消防部队主导地位的措施。笔者认为:只要保障有力,在我国典型公共场所突发事件现场应急处置的过程中,组建一支以消防部队为主导的能够承担多种灾害紧急救援任务的专业化综合救援队伍是可行的,消防部队作为主导救援力量具有其他任何应急救援组织无可比拟的基础和条件。 相似文献